Purpose: Variability in outcome after carotid endarterectomy is well recognized. This study examines the importance of patient-related factors in determining outcome. Methods: Four hundred and sixty consecutive patients undergoing carotid endarterectomy for symptomatic severe (60% to 99%) internal carotid stenosis performed by one vascular surgeon have been studied prospectively. Patients were followed-up at 3, 6, 9, and 12 months and then yearly. Pre-, intra-, and perioperative details and follow-up information were entered on a database. Results: Multiple logistic regression identified a number of factors significantly associated with death and stroke. A history of crescendo transient ischemic attacks (TIAs) (p = 0.003, p = 0.0002) and being female (p = 0.03, p = 0.0001) were associated with both perioperative death and stroke within 30 days of operation, respectively. Deaths between 1 and 36 months were associated with ischemic heart disease (p = 0.03) and diabetes (p = 0.04), whereas stroke was associated with small internal carotid diameter (p = 0.02). The importance of symptoms at presentation on outcome was further emphasized by life-table analysis. In 98% of patients with amaurosis fugax, only 67% of those with crescendo TIAs were alive at 18 months (p < 0.01). The survival of patients with amaurosis was significantly better than those with TIAs (p < 0.01), transient stroke (p < 0.01), and progressive stroke (p < 0.05). Similarly, postoperative stroke was significantly more common for patients with crescendo TIAs than those with amaurosis (p < 0.01), established stroke (p < 0.05), and TIA (p < 0.05). Transient stroke was associated with a poor outcome, with only 66% of patients being alive at 36 months and 14% having suffered a stroke (p < 0.05 compared with established stroke). Conclusion: Presenting symptoms significantly predict outcome after carotid endarterectomy. This should be considered both in patient selection and comparison of patient series.